The final season of Fox's Bones will largely center on Brennan (Emily Deschanel) and Booth (David Boreanaz) trying to work through overarching conflicts in their lives.

Bones is officially over for another season, this time ending on a huge cliffhanger involving former Jeffersonian intern Zack Addy (Eric Millegan) returning and kidnapping Brennan. Now, heading into the show's 12th and final season, the series will be delving into what went wrong with Zack and much more.

Bones executive producer Michael Peterson spoke about this in a new interview with TV Insider.

"I think that's the big question: everyone is looking at [Zack], when we come back next season--what has happened?" Peterson teased. "If you look at the very end [of the finale], he has a very large scar across his forehead: what's the story behind that? He's been gone for a long, long time. As you very astutely said, being in a place where you're considered sick will have an impact on him. Who has he been hanging out with, what have their influences been? All of those things will need to be resolved."

As for Brennan and Booth in these final episodes, Peterson spoke about how both characters will deal with various conflicts they've had in past seasons.

"When we went in originally to Fox to pitch what we wanted to do, there's a new threat to Booth and Brennan, it's something that's actually borne out of Season 1. A lot of it has to do with the ghosts of the past, if you will," Peterson said. "Booth's arc is really about him seeking forgiveness, in a way, of the sins of the past; the kills he did back when he was a sniper. We're going to have someone from Booth's past pay him a visit and haunt him in an interesting way. We really are looking to resolve that. For Brennan, when we first meet her back in Season 1, it was all about finding her family. There are going to be some new twists and turns for Brennan as far as her search for family. We're looking to resolve Booth dealing with his past sins, if you will, and Brennan's quest to feel complete with her family. Those will be the big challenges in Season 12."

Bones season 12 will air at some point in 2017 on Fox. The series was pushed back from its original fall 2016 air date, with Fox putting its new show Pitch in its place. The final season will only have 12 episodes in total, a big drop from the usual 22.

Tags: Bones television fox